Swivel chair mounting



Nov. 10, 1936. w. F. HERoLD SWIVEL CHAIR MOUNTING Filed June 11, 1954 INV EN TOR.- 'WALTER HER ULD ATTORNEX Patented Nov. 1936 UNITED STATESPATENT OFFICE SWIVEL CHAIR MOUNTING Application June 11, 1934, SerialNo. 730,031

11 Claims.

The present invention relates to an improved swivel chair mounting, andhas for an object to provide a swivel mounting by means of which thechair Seat may be swiveled with a very easy action without effecting thevertical adjustment, and further to provide means by which the chairseat may be vertically adjusted with facility. A further object is toprovide adjustment means which may be readily turned to adjust l theheight of the seat without the necessity for withdrawing pins, springplungers or other such locking means, and which when a-djusted willremain in the adjusted position through frictional cooperation of theparts.

Another object is to provide a mounting in which the exposed part of thepost between the base and the chair seat support is stationary and freefrom grease or dirt, and further in which the adjustment parts areconcealed and are operable from the underside of the base, to the endthat the upper portion of the base will be free of parts that may soilor injure clothing coming in contact therewith and also lends itself tothe carrying out of more pleasing designs in the base.

Another object is to provide a swivel mounting in which the swivelsupport is self-centering so that side-play and looseness is eliminated,and Wear is automatically compensated.

It is particularly proposed in the present invention to provide atelescoping supporting post upon which the chair iron is swivellymounted, 'and which uniformly supports the iron in any position ofadjustment.

With the above and other objects in View an embodiment of the inventionis shown in the accompanying drawing, and this embodiment will behereinafter more fully described with reference thereto, and theinvention will be finally pointed out in the claims.

In the drawing:

Fig. l is a side elevation of a chair iron embodying the invention, theend portions of the spider arms and the support-post being broken away.

Fig. 2 is a top plan view, a portion of the top flange of one of thespider arms being broken away.

Fig. 3 is a rear elevation.

Fig. 4 is a vertical sectional view.

Fig. 5 is a reduced side elevation of a chair in which the base isdesigned to enclose the swivel mounting post.

Similar reference characters indicate correspending parts throughout theseveral figures of 55 the drawing.

Referring to the drawing, the. chair iron illustrated comprises a pairof angular cross-section spider arms i-iil adapted to be screwed to theunder side of a chair seat in the usual manner, and mounted for tiltingmovement upon a seat support or bracket li, which in accordance with theinvention is mounted for vertical adjustment and swiveling movement, Theparticular construction of the tilting mounting forms no part of theinvention, so that it is sufficient to merely state that the oneillustrated comprises a joint element of the type as disclosed in myco-pending patent application, S. N. 695,898, led October 3l, i933, inwhich an outer sleeve member i2 is secured with respect to the bracketH, an inner spindle element i3 is secured at its ends to the spider armsiii-Jil and an intermediate tubular resilient member I4 of rubber isdisposed between them under tension, and which normally retains thespider arms in contact with the forward stop i5 of the bracket whilepermitting tilting movement rearwardly against the inclined stop membersIS-l.

The seat support or bracket l is provided with a vertically disposedtubular post or bearing portion I7 having a transverse head portion i8closing its upper end, and within which head portion there is securedthe shank i9 of a pivot bearing stud 2li, the latter being of sphericalform and co-axial with the vertical axis of the post l l. Within ashouldered recess 2i at the lower end of the tubular post Il there isengaged a bearing ring 22.

The chair base 23, which is preferably of the usual type consisting offour radially extending downwardly curved legs, is provided with acentral cylindrical passage 24 in which is engaged and secured acylindrical tubular post 25. The lower end of this post is staked, as at26, or otherwise suitably secured to a plate 2l disposed at the lowerside of the chair base, and projects upwardly through the aperture of anapertured plate 28 disposed at the upper side of the chair base, theplates 2 and 23 being secured by tie rods 29 extending between themthrough the chair base.

The plate 2l is provided within the lower end of the post 25 with abearing aperture 3B in which the lower end of an adjustment screw-shaft3| is rotatably engaged. For this purpose the shaft 3| is provided witha ange 32 near its lower end forming a shoulder which engages upon awasher 33 disposed about the shaft at the upper side of the plate 2l,and a hand wheel or knob 34 has its hub 35 secured upon the downwardlyprojecting end of the shaft at the under side of the plate 21 by meansof a cotter-pin 36.

Within the post 25 there is telescopingly engaged a verticallyadjustable tubular telescoping extension member 31 having an internallythreaded nut 38 secured within its lower end which engages thescrew-shaft 3|. This nut is preferably secured in the extension memberby engaging a flange lip 39 at its lower end in a shouldered recess 40in the lower end of the extension member and swedging over the end ofthe extension member as at 4|. The upper end of the screw-shaft isprovided with a head which limits the upward adjustment of the extensionmember 31 and prevents the nut from leaving the screw-shaft. An annularrecess 42 is provided in the outer surface of the extension member 31 inwhich is engaged a split spring friction ring 43 engaging throughoutward spring pressure with the inner surface of the post 25.

At the upper end of the extension member 31 there is provided a bearingblock 44 having a shouldered shank 45 set into the opening of theextension member and provided with a spherical recess 46, in which thebearing stud 28 is adapted to seat in the assembled relation, the post25 being slidably and rotatably engaged with the bearing ring 22. Theseat support or bracket is retained upon the extension member, so thatit cannot be accidentally lifted off, by means of a set screw 41engaging an annular recess 48 provided in the extension member near itsupper end. The bearing block 44 is preferably formed of self-lubricatingmetal, as for instance oil impregnated bronze.

In the normal operation of the mounting the seat support or bracket willhave free swiveling movement about the post 25 and extension member 31,the friction produced between the nut 38 and screw-shaft 3| by theweight of the person seated in the chair being suicient to prevent anytendency of the extension member 31 to turn through the slight frictionproduced during rotation of the bearing stud 2|) in the bearing block44. The bearing ring 22 which takes side thrust engages the stationarypost 25 and therefore has no tendency to impart rotary movement to theadjustable parts of the mounting. When the chair seat is being adjustedthe weight of the person normally seated in the chair is removed, sothat there is very little friction between the nut 38 and thescrew-shaft 3|, and the latter may v therefore be readily turned. Duringthis operation the split spring ring 43 frictionally holds the extensionmember 31 against relative rotation with respect to the post 25, whileat the same time permitting it to have relative longitudinal movement.The adjustment screw 3| is completely concealed and protected from dustand dirt. It may be originally packed with grease, and thereafter willusually not require any further lubrication.

The chair iron seat support or bracket it will be observed is of verysimple form, and may be conveniently formed of cast metal, the onlyparts then requiring machining operations and tting being the bearingstud 20, ring 22 and set screw 41.

As shown in Fig. 5 the chair base 23 may be provided with a pedestalportion 23a forming a closure about the post 25. This is made possibleby the provision of the adjustment nut 34 at the bottom of the base, andobviously permits of the carrying out of more artistic designs than hasbeen heretofore possible with chairs in which the adjustment means wasarranged at the upper side of the base.

I have illustrated and d-escribed a preferred and satisfactoryembodiment of the invention, but it will be obvious that changes may bemade therein, within the spirit and scope thereof, as defined in theappended claims.

Having thus described my invention what I claim and desire to secure byLetters Patent is:-

l. In a swivel chair mounting, a chair seat support, a bearing portioncarried by said chair seat support, vertical thrust pivot bearing meanscarried by said bearing portion, side thrust annular bearing meanscarried by said bearing portion, a chair base, a fixed tubular postsecured to said base projecting upwardly and having sliding bearingrelatively to said annular bearing means to take side thrust, avertically adjustable member carried by said post, bearing means carriedby said member engaging said vertical thrust pivot bearing means, andmeans within said tubular post for effecting the vertical adjustment ofsaid member relative to said tubular post.

2. In a swivel chair mounting, a chair seat support, a tubular bearingportion carried by said chair seat support, vertical thrust pivotbearing means carried by said bearing portion, a chair base, a fixedpost secured to said base projecting upwardly and having sliding bearingin said tubular bearing portion to take side thrust, a verticallyadjustable member' carried by said post, bearing means carried by saidmember engaging said vertical thrust pivot bearing means, and means foreffecting the vertical adjustment of said member relative to said fixedpost.

3. In a swivel chair mounting, a chair seat support, a tubular bearingportion carried by said chair seat support, vertical thrust pivotbearing means carried by said bearing portion, a chair base, a fixedtubular post secured to said base projecting upwardly and having slidingbearing in said tubular bearing portion to take side thrust, avertically adjustable extension member carried within said tubular post,bearing means carried by said extension member engaging said verticalthrust pivot bearing means, and means for effecting the verticaladjustment of said extension member.

4. In a swivel chair mounting, a chair seat support having a tubularbearing portion, a centrally disposed vertical thrust pivot bearingprovided in said bearing portion, annular side thrust bearing means insaid bearing portion, a chair base, a tubular post secured to said baseprojecting upwardly and having sliding bearing in said side thrustbearing means, bearing means carried by said post and engaged by saidvertical thrust bearing, and adjustment screw within said post adaptedto be turned to affect the vertical adjustment of said bearing means.

5. In a swivel chair mounting, a chair seat support, a bearing portioncarried by said chair seat support, vertical thrust pivot bearing meanscarried by said bearing portion, a chair base, a Xed tubular postcarried by said base having sliding bearing relatively to said bearingportion and providing a vertically extending passage entirely above theunder side of said base, a vertically adjustable member within saidpassage having bearing engagement with said vertical thrust pivotbearing, and means for vertically adjusting said member comprising amanually operable rotatable member mounted at the underside of saidbase, threaded means entirely within said passage adapted to be rotatedby said rotatable member, and threaded means carried by said verticallyadjustable member entirely Within said passage and cooperating with saidrst threaded means whereby rotation of said rst threaded means impartsvertical movement'l to said second threaded means and said verticallyadjustable member.

6. In a swivel chair mounting, a chair seat support having a tubularbearing portion, a chair base, a tubular post secured to said baseprojecting upwardly and having sliding bearing in said tubular bearingportion, a telescoping extension slidably mounted in said tubular post,means for vertically adjusting said extension relative to said post, andbearing means carried at the upper end of said extension and engaged bysaid bearing portion.

7. In a swivel chair mounting, a chair seat support, a bearing portioncarried by said chair seat support, Vertical thrust pivot bearing meanscarried by said bearing portion, a chair base, la nxed tubular postcarried by said base having sliding bearing relatively to said bearingportion land providing a vertically extending passage entirely above theunder side of said base, a vertically adjustable member within saidpassage having bearing engagement with said vertical thrust pivotbearing, and means for vertically adjusting said member comprising amanually operable rotatable member mounted at the underside of saidbase, a vertically disposed screw entirely within said passage adaptedto be rotated by said rotatable member, and a nut carried by saidvertically adjustable member engaging said screw whereby rotation ofsaid screw imparts vertical movement to said nut and said verticallyadjustable member.

8. In a swivel chair mounting, a chair seat support having a tubularbearing portion, a chair base, a tubular post secured to said baseprojecting upwardly and having sliding bearing in said tubular bearingportion, a telesooping extension slidably mounted in said tubular post,a nut carried by said extension, a rotatable vertically disposed screwdisposed in said tubular post and engaging said nut for adjusting saidextension in said post, and manually operable means at the end of saidscrew and disposed at the underside of said base for turning said screw.

9. In a swivel chair mounting, a chair seat support having a bearingportion, a chair base, a tubular post secured to said base projectingupwardly, a telescoping extension slidably mounted in said tubular post,a nut carried by said extension, a manually rotatable verticallydisposed screw disposed in said tubular post and engaging said nut foradjusting said extension in said post, a friction ring disposed betweensaid post and said extension adapted to resist relative rotation betweenthem, and bearing means carried at the upper end of said extension andengaged by said bearing portion.

10. In a swivel chair mounting, a chair seat support, a bearing portioncarried by said chair seat support, a chair base, a tubular post securedto said base projecting upwardly, a telescoping extension memberslidably mounted in said tubular post, means for vertically adjustingsaid extension member, a spring friction ring disposed between said postand said extension member carried by one of them and engaging the otherunder spring pressure adapted to resist relative rotation between themwhile permitting relative vertical movement, and bearing means carriedat the upper end of said extension member and engaged by said bearingportion.

